Manufacturing method of structure including phase separation structure

Abstract

To provide a manufacturing method of a structure including a phase separation structure capable of improving positional deviation or line roughness of a cylinder structure and preferably forming an alignment mark.SOLUTION: Provided is a manufacturing method of a structure including a phase separation structure having the steps of: forming a layer including a block copolymer having a film thickness t by using a resin composition containing the block copolymer; and phase-separating the layer into a cylinder structure or a lamella structure. The film thickness t is set such that a relation with a cycle L0 of the block copolymer satisfies a specific expression.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a structure including a phase separation structure, a method for improving the misalignment of a cylinder structure and the formation of alignment marks, and a method for improving line roughness and the formation of alignment marks.

Background Art

[0002] In recent years, with the further miniaturization of large-scale integrated circuits (LSIs), technologies for processing more delicate structures have been demanded. In response to such demands, technologies for forming finer patterns have been developed by utilizing a phase separation structure formed by self-organization (DSA) of block copolymers in which blocks that are incompatible with each other are bonded (see, for example, Patent Document 1).

[0003] The above block copolymer separates (phase separates) in microscopic regions due to the repulsion between blocks that are incompatible with each other, and by performing heat treatment or the like, a structure having a regular periodic structure is formed. Specific examples of this periodic structure include cylinders (columnar), lamellae (plate-like), spheres (spherical), and the like.

[0004] In order to utilize the phase separation structure of the block copolymer, it is essential to form a self-organized nanostructure formed by microphase separation only in a specific region and to arrange it in a desired direction. In order to achieve these position control and orientation control, processes such as graphoepitaxy that controls the phase separation pattern by a guide pattern and chemical epitaxy that controls the phase separation pattern by differences in the chemical state of the substrate have been proposed (see, for example, Non-Patent Document 1).

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Non-Patent Documents

[0006] [Non-Patent Document 1] Proc. SPIE 7637, Alternative Lithographic Technologies II, 76370G (1 April 2010) [Summary of the Invention] [Problems to be Solved by the Invention]

[0007] When forming a line-and-space (LS) pattern using a lamellar structure, it is required to improve line roughness such as line edge roughness (LER). Further, when forming a contact hole (CH) pattern using a cylinder structure, the cylinder structure is formed at a position corresponding to the hexagonal closest-packed structure in plan view, but it is necessary to suppress the formation with a deviation in position.

[0008] Further, when performing DSA pattern formation for device construction, alignment (substrate position control) is required in the lithography process used in combination with DSA pattern formation. For alignment, it is necessary that an alignment mark for recognizing the position is formed well together with the DSA pattern.

[0009] The present invention has been made in view of the above circumstances, and an object thereof is to provide a method for manufacturing a structure including a phase separation structure that can improve the positional deviation or line roughness of a cylinder structure and can form an alignment mark well. Another object is to provide a method for improving the positional deviation of a cylinder structure and alignment mark formation, and a method for improving line roughness and alignment mark formation. [Means for Solving the Problems]

[0010] To solve the above problems, the inventors of the present invention conducted intensive studies. As a result, they found that by setting the film thickness of the layer containing the block copolymer so that the relationship with the period of the block copolymer satisfies a specific formula, the above problems can be solved, and the present invention has been completed. Specifically, the present invention provides the following.

[0011] A first aspect of the present invention is a method for manufacturing a structure including a phase separation structure, including: step (a1) of forming a layer containing the block copolymer with a film thickness t (nm) on a substrate using a resin composition containing the block copolymer; step (a2) of phase-separating the layer into a cylinder structure; in step (a1), the film thickness t is set so that the relationship with the period L 0 (nm) of the block copolymer satisfies the following formula (a). (2L 0 +(3 0.5 / 2)L 0 ×n)×0.9 ≦ t ≦ (2L 0 +(3 0.5 / 2)L 0 ×n)×1.1 (a) (In formula (a), n is an integer of 0 or more and 3 or less.)

[0012] A second aspect of the present invention is a method for improving the positional deviation of a cylinder structure and the formation of alignment marks, including: step (a1) of forming a layer containing the block copolymer with a film thickness t (nm) on a substrate using a resin composition containing the block copolymer; step (a2) of phase-separating the layer into a cylinder structure; in step (a1), the film thickness t is set so that the relationship with the period L 0 (nm) of the block copolymer satisfies the following formula (a). (2L 0 +(3 0.5 / 2)L 0 ×n)×0.9 ≦ t ≦ (2L 0 +(3 0.5 / 2)L 0 ×n)×1.1 (a) (In formula (a), n is an integer of 0 or more and 3 or less.)

[0013] A third aspect of the present invention includes a step (b1) of forming a layer containing the block copolymer with a film thickness t (nm) on a substrate using a resin composition containing the block copolymer, and a step (b2) of phase-separating the layer into a lamellar structure, wherein in step (b1), the film thickness t is set so that the relationship with the period L 0 (nm) of the block copolymer satisfies the following formula (b), which is a method for manufacturing a structure including a phase-separated structure. (1.5L 0 +0.5L 0 ×m)×0.95 ≦ t ≦ (1.5L 0 +0.5L 0 ×m)×1.05 (b) (In formula (b), m is an integer of 0 or more and 5 or less.)

[0014] A fourth aspect of the present invention includes a step (b1) of forming a layer containing the block copolymer with a film thickness t (nm) on a substrate using a resin composition containing the block copolymer, and a step (b2) of phase-separating the layer into a lamellar structure, wherein in step (b1), the film thickness t is set so that the relationship with the period L 0 (nm) of the block copolymer satisfies the following formula (b), which is a method for improving line roughness and alignment mark formation. (1.5L 0 +0.5L 0 ×m)×0.95 ≦ t ≦ (1.5L 0 +0.5L 0 ×m)×1.05 (b) (In formula (b), m is an integer of 0 or more and 5 or less.) [Advantages of the Invention]

[0015] According to the present invention, it is possible to provide a method for manufacturing a structure including a phase separation structure that can improve the misalignment or line roughness of a cylinder structure and can favorably form an alignment mark. Further, it is possible to provide a method for improving the misalignment and alignment mark formation of a cylinder structure, and a method for improving the line roughness and alignment mark formation.

Brief Description of the Drawings

[0016]

Figure 1

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Embodiments for Carrying Out the Invention

[0017] Hereinafter, embodiments of the present invention will be described in detail. However, the present invention is not limited to the following embodiments at all, and can be implemented with appropriate modifications within the scope of the object of the present invention.

[0018] In this specification, "aliphatic" is a relative concept with respect to aromatic, and means a group, compound, etc. that does not have aromaticity. "Alkyl group" means a linear or branched monovalent saturated hydrocarbon group unless otherwise specified. The same applies to the alkyl group in an alkoxy group. "Cycloalkyl group" means a monocyclic cyclic saturated hydrocarbon group unless otherwise specified. Unless otherwise specified, the "alkylene group" means a linear or branched divalent saturated hydrocarbon group. The "alkyl halide group" means a group in which some or all of the hydrogen atoms of the alkyl group are substituted with halogen atoms. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. The "fluorinated alkyl group" or "fluorinated alkylene group" means a group in which some or all of the hydrogen atoms of the alkyl group or alkylene group are substituted with fluorine atoms. The "structural unit" means a monomer unit (monomeric unit) that constitutes a high molecular compound (resin, polymer, copolymer). The "derived structural unit" means a structural unit formed by the cleavage of an ethylenic double bond or a cyclic ether. When it is described as "may have a substituent", it includes both the case of substituting a hydrogen atom (-H) with a monovalent group and the case of substituting a methylene group (-CH 2 -) with a divalent group. "Exposure" means the entire irradiation of radiation. Unless otherwise specified, the "α-position (α-carbon atom)" means the carbon atom to which the side chain of the block copolymer is bonded. The "α-carbon atom" of the methyl methacrylate unit means the carbon atom to which the carbonyl group of methacrylic acid is bonded. The "α-carbon atom" of the styrene unit means the carbon atom to which the benzene ring is bonded. Unless otherwise specified, the "number average molecular weight" (Mn) means the number average molecular weight in terms of standard polystyrene measured by size exclusion chromatography. Unless otherwise specified, the "weight average molecular weight" (Mw) means the weight average molecular weight in terms of standard polystyrene measured by size exclusion chromatography. When the value of Mn or Mw is attached with the unit (gmol -1 ), the value represents the molar mass. In this specification, depending on the structure represented by a chemical formula, there may be an asymmetric carbon, and enantiomers or diastereomers may exist. In that case, those isomers are represented by one formula. Those isomers may be used alone or as a mixture. In this specification, the "period of the structure" means the period of the phase structure observed when the structure of the phase separation structure is formed, and refers to the sum of the lengths of the respective phases that are immiscible with each other. When the phase separation structure forms a cylinder structure perpendicular to the substrate surface, the period of the structure (L 0 ) is the center-to-center distance (pitch) between two adjacent cylinder structures. The period of the structure (L 0 ) is known to be determined by the degree of polymerization N and the intrinsic polymerization characteristics such as the Flory-Huggins interaction parameter χ. That is, the larger the product "χ·N" of χ and N, the greater the mutual repulsion between different blocks in the block copolymer. For this reason, when χ·N>10.5 (hereinafter referred to as the "strength separation limit point"), the repulsion between different types of blocks in the block copolymer is large, and the tendency for phase separation to occur becomes strong. And at the strength separation limit point, the period of the structure is approximately N 2 / 3 ·χ 1 / 6 and the relationship of the following formula (cy) holds. That is, the period of the structure is proportional to the degree of polymerization N that correlates with the molecular weight and the molecular weight ratio between different blocks. L 0 ∝ a·N 2 / 3 ·χ 1 / 6 ···(cy) [In the formula, L 0 represents the period of the structure. a is a parameter indicating the size of the monomer. N represents the degree of polymerization. χ is the interaction parameter, and the larger this value, the higher the phase separation performance.] Therefore, by adjusting the composition and total molecular weight of the block copolymer, the period of the structure (L 0 ) can be adjusted.

[0019] In view of the above problems, the inventors have found that the larger the film thickness of the layer containing the block copolymer, the more the misalignment of the cylinder structure and the line roughness can be improved. On the other hand, the alignment marks may or may not be formed well depending on the film thickness. In DSA pattern formation, alignment marks are generally formed by combining a horizontal alignment region and a vertical alignment region by utilizing the orientation of the block copolymer. For example, in FIG. 1, an alignment mark 10 is formed such that a rectangular horizontal alignment region 11 covers the periphery of a rectangular vertical alignment region 12 in a plan view. In the alignment marks that are not formed well, unnecessary irregularities such as a substantially circular shape are formed in the horizontal alignment region. Note that "horizontal alignment" in the specification of the present application means an alignment state in which a horizontal interface is formed with respect to the surface of the substrate in a phase-separated state. Usually, the direction perpendicular to the direction in which gravity acts is called the horizontal direction. However, in the "horizontal alignment" in the specification of the present application, the interface between the phases formed by phase separation does not have to be a horizontal plane. Also, "vertical alignment" in the specification of the present application means an alignment state in which a vertical interface is formed with respect to the surface of the substrate in a phase-separated state. The inventors of the present invention have found that when the film thickness is set so that the relationship with L satisfies a specific formula, unnecessary irregularities are not formed in the horizontal alignment region and the alignment marks can be formed well. The reason is speculated as follows. 0 When the film thickness is set so that the relationship with L satisfies a specific formula, unnecessary irregularities are not formed in the horizontal alignment region and the alignment marks can be formed well. The reason is speculated as follows. When the lamellar structure is horizontally aligned, as shown in FIG. 2(a), the phase-separated phases are alternately arranged in the vertical direction in the vicinity of a cycle of 0.5L. 0 Therefore, when the film thickness is set in the vicinity of a cycle of 0.5L, unnecessary irregularities are not formed. On the other hand, when the film thickness is set outside the vicinity of the above cycle, as shown in FIG. 3, a region where there is no phase-separation structure for one cycle is generated, and unnecessary irregularities are formed. 0 Therefore, when the film thickness is set in the vicinity of a cycle of 0.5L, unnecessary irregularities are not formed. On the other hand, when the film thickness is set outside the vicinity of the above cycle, as shown in FIG. 3, a region where there is no phase-separation structure for one cycle is generated, and unnecessary irregularities are formed. Also, when the cylinder structure is horizontally aligned, as shown in FIG. 2(b), the cylinder structures are arranged in the vertical direction in the vicinity of a cycle of (3 0.5 / 2)L 0 Therefore, (30.5 / 2)L 0 When the film thickness is set near the above cycle, unnecessary unevenness is not formed. On the other hand, when the film thickness is set outside the vicinity of the above cycle, unnecessary unevenness is formed as in the lamellar structure.

[0020] ≪First Aspect: Method for Manufacturing a Structure Including a Phase Separation Structure (Cylinder Structure)≫ The manufacturing method according to the first aspect includes a step (a1) of forming a layer containing the block copolymer with a film thickness t (nm) on a substrate using a resin composition containing the block copolymer, and a step (a2) of phase-separating the layer into a cylinder structure. In step (a1), the film thickness t is set so that the relationship with the period L 0 (nm) of the block copolymer satisfies the following formula (a). (2L 0 +(3 0.5 / 2)L 0 ×n)×0.9 ≦ t ≦ (2L 0 +(3 0.5 / 2)L 0 ×n)×1.1 (a) (In formula (a), n is an integer from 0 to 3.)

[0021] Hereinafter, the manufacturing method of the structure including such a phase separation structure will be specifically described with reference to FIG. 4. However, the manufacturing method of the structure including the phase separation structure according to the first aspect is not limited to the embodiment specifically shown in FIG. 4.

[0022] FIG. 4 shows an example of an embodiment of the manufacturing method of the structure including the phase separation structure. In the embodiment shown in FIG. 4, first, an underlayer agent is applied on a substrate 41 to form a layer 42 made of a neutralization film (FIG. 4(I)). Although not shown in FIG. 4, in the region to be horizontally aligned at the alignment mark, a film having affinity with any block constituting the block copolymer is formed, and in the region to be vertically aligned, a neutralization film is formed. Next, a resin composition for forming a phase separation structure is applied onto the layer 42 made of a neutralization film or onto the region where the alignment marks are formed, to form a layer (BCP layer) 43 containing a block copolymer with a film thickness of t (nm) (Fig. 4 (II); the above is step (a1)). Next, heating is performed for annealing treatment to phase-separate the BCP layer 43 into a phase 43a and a phase 43b (Fig. 4 (III); step (a2)). According to the manufacturing method of such an embodiment, that is, the manufacturing method having steps (a1) and (a2), a structure 43' including a phase separation structure is manufactured on the substrate 41 on which the layer 42 made of a neutralization film is formed. Further, alignment marks having a horizontal alignment region and a vertical alignment region are formed.

[0023] <Step (a1)> In step (a1), a resin composition for forming a phase separation structure is applied onto the substrate 41 to form a BCP layer 43 with a film thickness of t (nm).

[0024] As long as the resin composition can be applied onto its surface, the type of the substrate 41 is not particularly limited. For example, substrates made of inorganic substances such as silicon, metals (copper, chromium, iron, aluminum, etc.), glass, titanium oxide, silica, mica, etc.; substrates made of oxides such as SiO 2 substrates made of nitrides such as SiN; substrates made of oxynitrides such as SiON; substrates made of organic substances such as acrylic resin, polystyrene, cellulose, cellulose acetate, phenolic resin, etc. Among these, a silicon substrate (Si substrate) or a metal substrate is preferable, a Si substrate or a copper substrate (Cu substrate) is more preferable, and a Si substrate is particularly preferable. The size and shape of the substrate 41 are not particularly limited. The substrate 41 does not necessarily have a smooth surface, and substrates of various shapes can be appropriately selected. For example, substrates having a curved surface, flat plates with an uneven surface, substrates in the shape of flakes, etc. can be mentioned.

[0025] An inorganic-based and / or organic-based film may be provided on the surface of the substrate 41. Examples of the inorganic film include an inorganic antireflection film (inorganic BARC). Examples of the organic film include an organic antireflection film (organic BARC). The inorganic film can be formed, for example, by applying an inorganic antireflection film composition such as a silicon-based material onto a support and then baking it or the like. The organic film can be formed, for example, by applying a material for forming an organic film in which a resin component or the like constituting the film is dissolved in an organic solvent onto a substrate using a spinner or the like, and preferably baking it under heating conditions of 200 to 300°C, preferably for 30 to 300 seconds, more preferably for 60 to 180 seconds. This material for forming an organic film does not necessarily require sensitivity to light or an electron beam like a resist film, and may or may not have sensitivity. Specifically, a resist or resin generally used in the manufacture of semiconductor elements and liquid crystal display elements can be used. In addition, in order to be able to transfer a pattern of a phase separation structure to form an organic film pattern, the material for forming an organic film is preferably a material that can form an organic film that can be etched, particularly dry-etched. Among them, it is preferably a material that can form an organic film that can be etched such as oxygen plasma etching. Such a material for forming an organic film may be a material conventionally used for forming an organic film such as organic BARC. For example, the AR series manufactured by Nissan Chemical Industries, Ltd., the AR series manufactured by Rohm and Haas, the SWK series manufactured by Tokyo Ohka Kogyo Co., Ltd., etc. can be mentioned.

[0026] In the embodiment shown in FIG. 4, first, a base agent is applied onto a substrate 41 to form a layer 42 made of a neutralization film. Thus, it is preferable to provide a layer 42 made of a neutralization film on the substrate 41. Thereby, the hydrophilic-hydrophobic balance between the surface of the substrate 41 and a layer (BCP layer) 43 containing a block copolymer can be achieved. Also, in the region to be horizontally aligned in the alignment mark, it is preferable to form a layer made of a film having an affinity with any one of the blocks of the block copolymer on the substrate 41, and in the region to be vertically aligned, it is preferable to form a layer made of a neutralizing film on the substrate 41. Thereby, each region can be aligned as intended.

[0027] As the underlayer agent, a resin composition can be used. The resin composition for the underlayer agent can be appropriately selected from conventionally known resin compositions used for thin film formation according to the types of the blocks constituting the block copolymer. The resin composition for the underlayer agent may be, for example, a thermopolymerizable resin composition, or a photosensitive resin composition such as a positive resist composition or a negative resist composition. Alternatively, a compound may be used as a surface treatment agent, and a non-polymerizable film formed by applying the compound may be used as the neutralizing film. For example, a siloxane-based organic monomolecular film formed using phenethyltrichlorosilane, octadecyltrichlorosilane, hexamethyldisilazane, etc. as the surface treatment agent can also be suitably used as the neutralizing film.

[0028] As the resin composition for the underlayer agent, for example, a composition containing a resin having both styrene and methyl methacrylate as constituent units, or a compound or composition containing both a site highly affinity with styrene such as an aromatic ring and a site highly affinity with methyl methacrylate (a highly polar functional group, etc.) is preferably used. Examples of the resin having both styrene and methyl methacrylate as constituent units include a random copolymer of styrene and methyl methacrylate, an alternating polymer of styrene and methyl methacrylate (a polymer in which each monomer is copolymerized alternately), and the like. In addition, examples of the composition containing both a site highly compatible with styrene and a site highly compatible with methyl methacrylate include, for example, a composition containing a resin obtained by polymerizing at least a monomer having an aromatic ring and a monomer having a highly polar functional group. Examples of the monomer having an aromatic ring include aryl groups obtained by removing one hydrogen atom from an aromatic hydrocarbon ring such as a phenyl group, a biphenyl group, a fluorenyl group, a naphthyl group, an anthryl group, and a phenanthryl group, or monomers having a heteroaryl group in which some of the carbon atoms constituting the ring of these groups are substituted with heteroatoms such as an oxygen atom, a sulfur atom, and a nitrogen atom. Examples of the monomer having a highly polar functional group include monomers having a trimethoxysilyl group, a trichlorosilyl group, an epoxy group, a glycidyl group, a carboxy group, a hydroxy group, a cyano group, and a hydroxyalkyl group in which some of the hydrogen atoms of an alkyl group are substituted with a hydroxy group. In addition, examples of the compound containing both a site highly compatible with styrene and a site highly compatible with methyl methacrylate include compounds containing both an aryl group and a highly polar functional group such as phenethyltrichlorosilane, and compounds containing both an alkyl group and a highly polar functional group such as an alkylsilane compound.

[0029] The resin composition for the undercoat can be produced by dissolving the aforementioned resin in a solvent. Such a solvent may be any solvent that can dissolve each component to be used and form a uniform solution. For example, the same solvents as the organic solvent components exemplified in the description of the resin composition for forming a phase separation structure can be mentioned.

[0030] The method for forming the layer 42 made of a neutralization film by applying the undercoat on the substrate 41 is not particularly limited, and the layer 42 made of a neutralization film can be formed by a conventionally known method. For example, the undercoat can be applied on the substrate 41 by a conventionally known method such as spin coating or using a spinner to form a coating film, and then dried to form the layer 42 made of a neutralization film. As a method for drying the coating film, it is only necessary to be able to volatilize the solvent contained in the primer, and examples thereof include a baking method. At this time, the baking temperature is preferably 80 to 300 °C, more preferably 180 to 270 °C, and even more preferably 220 to 250 °C. The baking time is preferably 30 to 500 seconds, and more preferably 60 to 400 seconds. The thickness of the layer 42 made of the neutralization film after drying the coating film is preferably about 10 to 100 nm, and more preferably about 40 to 90 nm.

[0031] Before forming the layer 42 made of the neutralization film on the substrate 41, the surface of the substrate 41 may be washed in advance. By washing the surface of the substrate 41, the coatability of the primer is improved. As the cleaning treatment method, a conventionally known method can be used, and examples thereof include oxygen plasma treatment, ozone oxidation treatment, acid-base treatment, chemical modification treatment, and the like.

[0032] After forming the layer 42 made of the neutralization film, if necessary, the layer 42 made of the neutralization film may be rinsed with a rinse liquid such as a solvent. By this rinsing, uncrosslinked portions and the like in the layer 42 made of the neutralization film are removed, so that the affinity with at least one block constituting the block copolymer is improved, and a phase separation structure oriented in the direction perpendicular to the surface of the substrate 41 is easily formed. In addition, the rinse liquid may be any liquid that can dissolve the uncrosslinked portion, and solvents such as propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME), ethyl lactate (EL), or a commercially available thinner liquid can be used. Further, after the cleaning, post-baking may be performed to volatilize the rinse liquid. The temperature conditions for this post-baking are preferably 80 to 300 °C, more preferably 100 to 270 °C, and even more preferably 120 to 250 °C. The baking time is preferably 30 to 500 seconds, and more preferably 60 to 240 seconds. The thickness of the layer 42 made of the neutralization film after such post-baking is preferably about 1 to 10 nm, and more preferably about 2 to 7 nm.

[0033] Next, a resin composition for forming a phase separation structure described later is applied onto the layer 42 made of a neutralization film or onto the region where the alignment marks are formed, to form a layer (BCP layer) 43 containing a block copolymer with a film thickness t (nm). The method for forming the BCP layer 43 is not particularly limited. For example, a method of applying a resin composition for forming a phase separation structure onto the layer 42 made of a neutralization film or onto the region where the alignment marks are formed to form a coating film and then drying it by a conventionally known method such as spin coating or using a spinner can be mentioned. As a method for drying the coating film of the resin composition for forming a phase separation structure, it is only necessary to be able to volatilize the organic solvent component contained in the resin composition for forming a phase separation structure. For example, a method of baking can be mentioned.

[0034] In this embodiment, the film thickness t of the BCP layer 43 is set so that the relationship with the period L 0 (nm) of the block copolymer satisfies the following formula (a). (2L 0 +(3 0.5 / 2)L 0 ×n)×0.9≦t≦(2L 0 +(3 0.5 / 2)L 0 ×n)×1.1 (a) (In formula (a), n is an integer of 0 or more and 3 or less.)

[0035] By setting it to a thick film (2L 0 ×0.9 or more), the misalignment of the cylinder structure is improved, and by setting the film thickness in the vicinity of the cycle of (3 0.5 / 2)L 0 , good alignment marks are formed.

[0036] The film thickness t of the BCP layer 43 means the thickness of the layer containing the block copolymer after drying the coating film of the resin composition for forming a phase separation structure.

[0037] From the viewpoint of easily improving the misalignment of the cylinder structure, n is preferably an integer of 1 or more and 3 or less.

[0038] The film thickness t of the BCP layer 43 is not particularly limited as long as the above formula (a) is satisfied. For example, it is 40 to 180 nm, or 60 to 160 nm.

[0039] The method for adjusting the film thickness of the BCP layer 43 is not particularly limited. Examples include adjusting the concentration of the block copolymer in the resin composition for forming the phase separation structure, or adjusting the rotation speed when applying using, for example, the spin coating method.

[0040] <Process (a2)> In process (a2), the BCP layer 43 formed on the substrate 41 is phase-separated into a cylinder structure. For example, by heating the substrate 41 after process (a1) and performing an annealing treatment, a structure 43' including a phase separation structure phase-separated into phases 43a and 43b is manufactured. In subsequent processes, at least a part of the surface of the substrate 41 is exposed by selectively removing the phases. Also, a horizontally oriented phase separation structure is obtained in the horizontal alignment region of the alignment mark, and a vertically oriented phase separation structure is obtained in the vertical alignment region. The temperature condition of the annealing treatment is preferably equal to or higher than the glass transition temperature of the block copolymer used and lower than the thermal decomposition temperature. For example, in the case of a polystyrene-polymethyl methacrylate (PS-PMMA) block copolymer (weight average molecular weight 5000 to 100000), 180 to 270 °C is preferable, 200 to 270 °C is more preferable, and 220 to 260 °C is even more preferable. The heating time is preferably 1 minute to 1 hour, more preferably 2 to 45 minutes, and even more preferably 5 to 30 minutes. Also, the annealing treatment is preferably performed in a gas with low reactivity such as nitrogen.

[0041] <Optional process> The method for manufacturing a structure including a phase separation structure is not limited to the above-described embodiments, and may have processes (optional processes) other than process (a1) and process (a2).

[0042] Examples of such arbitrary processes include a process of selectively removing a phase composed of at least one type of block among the blocks constituting the block copolymer in the BCP layer 43 (hereinafter referred to as "process (a3)"), a guide pattern formation process, and the like.

[0043] ·Regarding process (a3) In process (a3), a phase composed of at least one type of block among the blocks constituting the block copolymer in the BCP layer 43 formed on a layer 42 made of a neutralization film or the like is selectively removed. As a result, a fine pattern (polymer nanostructure) is formed.

[0044] Examples of methods for selectively removing a phase composed of a block include a method of performing oxygen plasma treatment on the BCP layer, a method of performing hydrogen plasma treatment, and the like. In the following, among the blocks constituting the block copolymer, the block that is not selectively removed is referred to as the P A block, and the block that is selectively removed is referred to as the P B block. For example, after phase-separating a layer containing a PS-PMMA block copolymer, by performing oxygen plasma treatment, hydrogen plasma treatment, or the like on the BCP layer, the phase composed of PMMA is selectively removed. In this case, the PS portion is the P A block, and the PMMA portion is the P B block.

[0045] FIG. 5 shows an example of an embodiment of process (a3). In the embodiment shown in FIG. 5, by performing oxygen plasma treatment on the structure 43' manufactured on the substrate 41 in process (a2), the phase 43a is selectively removed, and a pattern (polymer nanostructure) composed of the separated phase 43b is formed. In this case, the phase 43b is a phase composed of the P A block, and the phase 43a is a phase composed of the P B block.

[0046] The substrate 41 on which the pattern is formed by the phase separation of the BCP layer 43 as described above can be used as it is, but by further heating, the shape of the pattern (polymer nanostructure) on the substrate 41 can also be changed. The temperature condition for heating is preferably equal to or higher than the glass transition temperature of the block copolymer to be used and lower than the thermal decomposition temperature. Further, the heating is preferably performed in a gas with low reactivity such as nitrogen.

[0047] ·Regarding the guide pattern formation step In the method for manufacturing a structure including a phase separation structure, a step of providing a guide pattern in a layer made of a neutralization film (guide pattern formation step) may be included. Thereby, control of the arrangement structure of the phase separation structure becomes possible. For example, even in the case of a block copolymer in which a random fingerprint-like phase separation structure is formed when no guide pattern is provided, by providing a groove structure of a resist film in a layer made of a neutralization film, a phase separation structure oriented along the groove can be obtained. Further, when the surface of the guide pattern has an affinity with any of the blocks constituting the block copolymer, a phase separation structure oriented in a direction perpendicular to the surface of the support is likely to be formed.

[0048] The guide pattern can be formed using, for example, a resist composition. The resist composition for forming the guide pattern can generally be appropriately selected from resist compositions generally used for forming resist patterns and modified products thereof, and a resist composition having an affinity with any block constituting the block copolymer. As the resist composition, it may be either a positive resist composition for forming a positive pattern in which the exposed portion of the resist film is dissolved and removed or a negative resist composition for forming a negative pattern in which the unexposed portion of the resist film is dissolved and removed, but a negative resist composition is preferred. As the negative resist composition, for example, it contains an acid generator and a base material component whose solubility in a developer containing an organic solvent decreases due to the action of an acid, and the base material component contains a resin component having a structural unit that decomposes due to the action of an acid and increases in polarity. After the resin composition for forming a phase separation structure is poured onto the layer made of the neutralization film on which the guide pattern is formed, an annealing treatment is performed to cause phase separation. For this reason, as the resist composition for forming the guide pattern, a resist composition capable of forming a resist film excellent in solvent resistance and heat resistance is preferred.

[0049] <Resin composition for forming phase separation structure> The resin composition for forming a phase separation structure used in the manufacturing method according to the first aspect contains a block copolymer.

[0050] (Block copolymer) A block copolymer is a polymer in which a plurality of types of blocks (partial constituent components in which the same type of structural unit is repeatedly bonded) are bonded. The number of blocks constituting the block copolymer may be two or three or more. The plurality of types of blocks constituting the block copolymer are not particularly limited as long as they are a combination in which phase separation occurs, but it is preferably a combination of blocks that are incompatible with each other. Further, it is preferable that the phase composed of at least one type of block among the plurality of types of blocks constituting the block copolymer is a combination that can be more easily and selectively removed than the phase composed of other types of blocks. Examples of the combination that can be easily and selectively removed include a block copolymer in which one type or two or more types of blocks having an etching selectivity ratio greater than 1 are bonded.

[0051] Examples of the block copolymer include a block copolymer in which a block of a structural unit having an aromatic group and a block of a structural unit derived from (α-substituted) acrylate are bonded; a block copolymer in which a block of a structural unit having an aromatic group and a block of a structural unit derived from (α-substituted) acrylic acid are bonded; a block copolymer in which a block of a structural unit having an aromatic group and a block of a structural unit derived from siloxane or a derivative thereof are bonded; a block copolymer in which a block of a structural unit derived from alkylene oxide and a block of a structural unit derived from (α-substituted) acrylate are bonded; a block copolymer in which a block of a structural unit derived from alkylene oxide and a block of a structural unit derived from (α-substituted) acrylic acid are bonded; a block copolymer in which a block of a structural unit containing a silsesquioxane structure and a block of a structural unit derived from (α-substituted) acrylate are bonded; a block copolymer in which a block of a structural unit containing a silsesquioxane structure and a block of a structural unit derived from (α-substituted) acrylic acid are bonded; a block copolymer in which a block of a structural unit containing a silsesquioxane structure and a block of a structural unit derived from siloxane or a derivative thereof are bonded, and the like.

[0052] Examples of the structural unit having an aromatic group include structural units having an aromatic group such as a phenyl group and a naphthyl group. Among them, a structural unit derived from styrene or a derivative thereof is preferable. Examples of styrene or its derivatives include styrene, α-methylstyrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, 2-ethylstyrene, 3-ethylstyrene, 4-ethylstyrene, 4-tert-butylstyrene, 4-n-octylstyrene, 2,4,6-trimethylstyrene, 4-methoxystyrene, 4-tert-butoxystyrene, 4-hydroxystyrene, 4-nitrostyrene, 3-nitrostyrene, 4-chlorostyrene, 4-fluorostyrene, 4-acetoxyvinylstyrene, 4-vinylbenzyl chloride, 1-vinylnaphthalene, 4-vinylbiphenyl, 1-vinyl-2-pyrrolidone, 9-vinylanthracene, vinylpyridine, and the like.

[0053] (α-substituted) acrylic acid means one or both of acrylic acid or acrylic acid in which the hydrogen atom bonded to the carbon atom at the α-position is substituted with a substituent. Examples of the substituent include an alkyl group having 1 to 5 carbon atoms. Examples of (α-substituted) acrylic acid include acrylic acid, methacrylic acid, and the like.

[0054] (α-substituted) acrylic acid ester means one or both of acrylic acid ester or acrylic acid ester in which the hydrogen atom bonded to the carbon atom at the α-position is substituted with a substituent. Examples of the substituent include an alkyl group having 1 to 5 carbon atoms. Examples of the (α-substituted) acrylate esters include acrylate esters such as methyl acrylate, ethyl acrylate, propyl acrylate, n-butyl acrylate, tert-butyl acrylate, cyclohexyl acrylate, octyl acrylate, nonyl acrylate, hydroxyethyl acrylate, hydroxypropyl acrylate, benzyl acrylate, anthracene acrylate, glycidyl acrylate, 3,4-epoxycyclohexylmethane acrylate, propyltrimethoxysilane acrylate, 2-hydroxy-3-(2,2,2-trifluoroethylsulfanyl)propyl acrylate; methacrylate esters such as methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, tert-butyl methacrylate, cyclohexyl methacrylate, octyl methacrylate, nonyl methacrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, benzyl methacrylate, anthracene methacrylate, glycidyl methacrylate, 3,4-epoxycyclohexylmethane methacrylate, propyltrimethoxysilane methacrylate, 2-hydroxy-3-(2,2,2-trifluoroethylsulfanyl)propyl methacrylate, etc. Among these, methyl acrylate, ethyl acrylate, tert-butyl acrylate, methyl methacrylate, ethyl methacrylate, and t-butyl methacrylate are preferred.

[0055] Examples of the siloxane or its derivative include dimethylsiloxane, diethylsiloxane, diphenylsiloxane, methylphenylsiloxane, etc. Examples of the alkylene oxide include ethylene oxide, propylene oxide, isopropylene oxide, butylene oxide, etc. As the silsesquioxane structure-containing structural unit, a cage-type silsesquioxane structure-containing structural unit is preferred. Examples of the monomer providing the cage-type silsesquioxane structure-containing structural unit include compounds having a cage-type silsesquioxane structure and a polymerizable group.

[0056] Among these, as the block copolymer, those containing a block of a structural unit having an aromatic group and a block of a structural unit derived from (α-substituted) acrylic acid or (α-substituted) acrylic acid ester are preferable.

[0057] When obtaining a cylinder-shaped phase separation structure oriented in a direction perpendicular to the substrate surface, the mass ratio of the structural unit having an aromatic group to the structural unit derived from (α-substituted) acrylic acid or (α-substituted) acrylic acid ester is preferably 60:40 to 90:10, and more preferably 60:40 to 80:20. In addition, in the third aspect described later, when obtaining a lamellar phase separation structure oriented in a direction perpendicular to the substrate surface, the mass ratio of the structural unit having an aromatic group to the structural unit derived from (α-substituted) acrylic acid or (α-substituted) acrylic acid ester is preferably 35:65 to 60:40, and more preferably 40:60 to 60:40.

[0058] Examples of such block copolymers include a block copolymer having a block of a structural unit derived from styrene and a block of a structural unit derived from acrylic acid, a block copolymer having a block of a structural unit derived from styrene and a block of a structural unit derived from methyl acrylate, a block copolymer having a block of a structural unit derived from styrene and a block of a structural unit derived from ethyl acrylate, a block copolymer having a block of a structural unit derived from styrene and a block of a structural unit derived from t-butyl acrylate, a block copolymer having a block of a structural unit derived from styrene and a block of a structural unit derived from methacrylic acid, a block copolymer having a block of a structural unit derived from styrene and a block of a structural unit derived from methyl methacrylate, a block copolymer having a block of a structural unit derived from styrene and a block of a structural unit derived from ethyl methacrylate, a block copolymer having a block of a structural unit derived from styrene and a block of a structural unit derived from t-butyl methacrylate, a block copolymer having a block of a structural unit containing a cage-type silsesquioxane (POSS) structure and a block of a structural unit derived from acrylic acid, a block copolymer having a block of a structural unit containing a cage-type silsesquioxane (POSS) structure and a block of a structural unit derived from methyl acrylate, and the like. In this embodiment, in particular, it is preferable to use a block copolymer (PS-PMMA block copolymer) having a block of a structural unit derived from styrene (PS) and a block of a structural unit derived from methyl methacrylate (PMMA).

[0059] The period L of the block copolymer 0 (nm) is preferably 20 to 50 nm, more preferably 25 to 45 nm.

[0060] The number average molecular weight (Mn) (in terms of polystyrene equivalent by gel permeation chromatography) of the block copolymer is preferably from 20,000 to 200,000, more preferably from 30,000 to 150,000, and even more preferably from 40,000 to 100,000.

[0061] The dispersity (Mw / Mn) of the block copolymer is preferably from 1.0 to 3.0, more preferably from 1.0 to 1.5, and even more preferably from 1.0 to 1.3. Herein, "Mw" represents the weight average molecular weight.

[0062] In the resin composition for forming a phase separation structure, one type of block copolymer may be used alone or two or more types may be used in combination. Further, in addition to the block copolymer, the same polymer as the polymer constituting any block may be added. In the resin composition for forming a phase separation structure, the content of the block copolymer may be adjusted according to the thickness of the layer containing the block copolymer to be formed and the like.

[0063] <Organic solvent component> The resin composition for forming a phase separation structure preferably contains an organic solvent. As the organic solvent component, any organic solvent that can dissolve each component to be used and form a uniform solution may be used. Conventionally, any organic solvent selected from known organic solvents as the solvent of the composition mainly composed of resin can be used.

[0064] Examples of the organic solvent component include lactones such as γ-butyrolactone; ketones such as acetone, methyl ethyl ketone, cyclohexanone, methyl-n-pentyl ketone, methyl isopentyl ketone, 2-heptanone; polyhydric alcohols such as ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol; monoacetates of polyhydric alcohols such as ethylene glycol monoacetate, diethylene glycol monoacetate, propylene glycol monoacetate, or dipropylene glycol monoacetate; monoalkyl ethers such as monomethyl ether, monoethyl ether, monopropyl ether, monobutyl ether of the polyhydric alcohols or the monoacetates of the polyhydric alcohols, or derivatives of polyhydric alcohols such as compounds having an ether bond such as monophenyl ether [Among these, propylene glycol monomethyl ether acetate (PGMEA) and propylene glycol monomethyl ether (PGME) are preferred]; cyclic ethers such as dioxane, and esters other than monoacetates of polyhydric alcohols and derivatives of the aforementioned polyhydric alcohols such as methyl lactate, ethyl lactate (EL), methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, ethyl pyruvate, methyl methoxypropionate, ethyl ethoxypropionate; aromatic organic solvents such as anisole, ethyl benzyl ether, cresyl methyl ether, diphenyl ether, dibenzyl ether, phenetole, butyl phenyl ether, ethyl benzene, diethyl benzene, pentyl benzene, isopropyl benzene, toluene, xylene, cymene, mesitylene, etc. The organic solvent component may be used alone or as a mixed solvent of two or more kinds. Among them, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME), cyclohexanone, and ethyl lactate (EL) are preferred.

[0065] The organic solvent component contained in the resin composition for forming a phase separation structure is not particularly limited. The organic solvent component is appropriately set according to the coating film thickness so that the concentration of the resin composition for forming a phase separation structure is a coatable concentration. The organic solvent component is generally used so that the solid content concentration of the resin composition for forming a phase separation structure is in the range of 0.2 to 70% by mass, preferably 0.2 to 50% by mass.

[0066] <Optional component> The resin composition for forming a phase separation structure may contain an optional component other than the block copolymer and the organic solvent component described above. Examples of the optional component include other resins, surfactants, dissolution inhibitors, plasticizers, stabilizers, colorants, anti-halation agents, dyes, sensitizers, base proliferators, basic compounds, and the like.

[0067] ≪Second aspect: Method for improving cylinder structure misalignment and alignment mark formation≫ The method according to the second aspect includes a step (a1) of forming a layer containing the block copolymer with a film thickness t (nm) on a substrate using a resin composition containing a block copolymer, and a step (a2) of phase-separating the layer into a cylinder structure. In step (a1), the film thickness t is set so that the relationship with the period L 0 (nm) of the block copolymer satisfies the following formula (a). (2L 0 +(3 0.5 / 2)L 0 ×n)×0.9 ≦ t ≦ (2L 0 +(3 0.5 / 2)L 0 ×n)×1.1 (a) (In formula (a), n is an integer of 0 or more and 3 or less.)

[0068] Details of this aspect are the same as those of the manufacturing method according to the first aspect.

[0069] ≪Third aspect: Method for manufacturing a structure including a phase separation structure (lamellar structure)≫ The manufacturing method according to the third aspect includes a step (b1) of forming a layer containing the block copolymer with a film thickness t (nm) on a substrate using a resin composition containing the block copolymer, and a step (b2) of phase-separating the layer into a lamellar structure. In step (b1), the film thickness t is set so that the relationship with the period L 0 (nm) of the block copolymer satisfies the following formula (b). (1.5L 0 +0.5L 0 ×m)×0.95≦t≦(1.5L 0 +0.5L 0 ×m)×1.05 (b) (In formula (b), m is an integer from 0 to 5.)

[0070] Hereinafter, the manufacturing method of the structure including such a phase-separated structure will be specifically described with reference to FIG. 6. However, the manufacturing method of the structure including the phase-separated structure according to the third aspect is not limited to the embodiment specifically shown in FIG. 6.

[0071] FIG. 6 shows an example of an embodiment of the manufacturing method of the structure including the phase-separated structure. In the embodiment shown in FIG. 6, first, a base agent is applied on a substrate 61 to form a layer 62 made of a neutralization film (FIG. 6(I)). Although not shown in FIG. 6, in the region to be horizontally aligned at the alignment mark, a film having an affinity with any block constituting the block copolymer is formed, and in the region to be vertically aligned, a neutralization film is formed. Next, a resin composition for forming a phase-separated structure is applied on the layer 62 made of the neutralization film or on the region where the alignment mark is formed to form a layer (BCP layer) 63 containing the block copolymer with a film thickness t (nm) (FIG. 6(II); the above is step (b1)). Next, heating and annealing treatment are performed to phase-separate the BCP layer 63 into phase 63a and phase 63b (FIG. 6(III); step (b2)). According to the manufacturing method of such an embodiment, that is, the manufacturing method having steps (b1) and (b2), a structure 63' including a phase separation structure is manufactured on a substrate 61 on which a layer 62 made of a neutralization film is formed. Further, an alignment mark having a horizontal alignment region and a vertical alignment region is formed.

[0072] In this aspect, the film thickness t of the BCP layer 63 is set so that the relationship with the period L 0 (nm) of the block copolymer satisfies the following formula (b). (1.5L 0 +0.5L 0 ×m)×0.95 ≦ t ≦ (1.5L 0 +0.5L 0 ×m)×1.05 (b) (In formula (b), m is an integer of 0 or more and 5 or less.)

[0073] By setting it to a thick film (1.5L 0 ×0.95 or more), line roughness is improved, and by setting the film thickness in the vicinity of the cycle of 0.5L 0 , a good alignment mark is formed.

[0074] From the viewpoint of easily improving line roughness, m is preferably an integer of 1 or more and 5 or less.

[0075] The film thickness t of the BCP layer 63 is not particularly limited as long as it satisfies the above formula (b), but for example, it is 30 to 150 nm, or 40 to 120 nm.

[0076] Other details of this aspect are the same as those of the manufacturing method according to the first aspect.

[0077] ≪Fourth Aspect: Method for Improving Line Roughness and Alignment Mark Formation≫ The method according to the fourth aspect includes a step (b1) of forming a layer containing the block copolymer with a film thickness t (nm) on a substrate using a resin composition containing a block copolymer, and a step (b2) of phase-separating the layer into a lamellar structure. In step (b1), the film thickness t is set to the period L of the block copolymer0 Set it so that the relationship with (nm) satisfies the following formula (b). (1.5L 0 +0.5L 0 ×m)×0.95 ≦ t ≦ (1.5L 0 +0.5L 0 ×m)×1.05 (b) (In formula (b), m is an integer from 0 to 5.)

[0078] The details of this aspect are the same as the manufacturing method according to the third aspect.

Example

[0079] Based on the examples, the present invention will be described in more detail, but the present invention is not limited by these examples.

[0080] Hereinafter, the block copolymers used in the examples and comparative examples will be described. BCP-A: A block copolymer consisting of a block of polystyrene (PS) and a block of polymethyl methacrylate (PMMA) (Mn: about 56000, Mw / Mn: 1.02, composition ratio of PS / PMMA (mol%): 50 / 50) BCP-B: A block copolymer consisting of a block of polystyrene (PS) and a block of polymethyl methacrylate (PMMA) (Mn: about 93000, Mw / Mn: 1.02, composition ratio of PS / PMMA (mol%): 65 / 35) BCP-C: A block copolymer consisting of a block of polystyrene (PS) and a block of polymethyl methacrylate (PMMA) (Mn: about 60000, Mw / Mn: 1.02, composition ratio of PS / PMMA (mol%): 65 / 35) BCP-D: A block copolymer composed of a block made of polystyrene and a block made of a random copolymer of 2-hydroxy-3-(2,2,2-trifluoroethylsulfanyl)propyl methacrylate (HFMA) and methyl methacrylate (Mn: about 49,000, Mw / Mn: 1.02, composition ratio (mol%) of styrene / HFMA / methyl methacrylate: 50 / 1 / 49, prepared with reference to the examples of JP-A-2022-20519) BCP-E: A block copolymer composed of a block made of polystyrene and a block made of a random copolymer of 2-hydroxy-3-(2,2,2-trifluoroethylsulfanyl)propyl methacrylate (HFMA) and methyl methacrylate (Mn: about 53,000, Mw / Mn: 1.02, composition ratio (mol%) of styrene / HFMA / methyl methacrylate: 65 / 1 / 34, prepared with reference to the examples of JP-A-2022-20519) BCP-F: A block copolymer composed of a block made of poly(4-ethylstyrene) (PES) and a block made of poly(methyl methacrylate) (PMMA) (Mn: about 51,000, Mw / Mn: 1.02, composition ratio (mol%) of PES / PMMA: 50 / 50) BCP-G: A block copolymer composed of a block made of poly(4-ethylstyrene) (PES) and a block made of poly(methyl methacrylate) (PMMA) (Mn: about 55,000, Mw / Mn: 1.02, composition ratio (mol%) of PES / PMMA: 65 / 35) BCP-H: A mixture (mass ratio: 40 / 40 / 13 / 7) of a block copolymer of a block made of polystyrene (PS) and a block made of poly(methyl methacrylate) (PMMA) (Mn: 96,000, composition ratio (mol%) of PS / PMMA: 65 / 35), a block copolymer of a block made of polystyrene (PS) and a block made of poly(methyl methacrylate) (PMMA) (Mn: 100,000, composition ratio (mol%) of PS / PMMA: 65 / 35), polystyrene (Mn: 2,000), and poly(methyl methacrylate) (Mn: 2,000) Note that even when the same block copolymer is used, L depends on the film thickness 0It changes slightly. Therefore, in the examples using the same type of block copolymer, L 0 In BCP-A to BCP-G, the molecular weight was finely adjusted so that L would be constant, and in BCP-H, the mixing ratio was finely adjusted. For example, in Comparative Example 1 and Examples 1 to 3, BCP-A is used, but L 0 The molecular weight was slightly changed so that it would be constant.

[0081] [Examples 1-1 to 1-7 and Comparative Examples 1-1 to 1-3] <Manufacture of a structure including a phase separation structure (cylinder structure)> A resin composition for forming a polystyrenated film, which is a propylene glycol monomethyl ether acetate (PGMEA) solution of a styrene / vinylbenzocyclobutene copolymer, was applied onto a 12-inch silicon wafer provided with an antireflection film using a spinner. A layer made of a polystyrenated film was formed on the silicon wafer by baking the applied film at 250 °C for 300 seconds. An ArF photoresist for liquid immersion exposure was applied onto the polystyrenated film to form an applied film. Then, the formed applied film was baked. Next, the baked applied film was exposed with an ArF liquid immersion exposure machine, and then post-exposure baking was performed. After development, plasma etching, subsequent resist stripping, and post-baking were carried out to form a pattern of the polystyrenated film. Thereafter, a resin composition for forming a neutralized film, which is a PGMEA solution of a styrene / methyl methacrylate / hydroxyethyl methacrylate copolymer, was applied onto the patterned polystyrenated film to form an applied film. The formed applied film was baked at 250 °C for 300 seconds, rinsed with OK73 thinner, and post-baked to obtain an evaluation guide substrate having a repeated guide pattern of a polystyrenated film and a neutralized film. In the region for forming an alignment mark, a polystyrenated film was formed in the horizontally oriented region, and a neutralized film was formed in the vertically oriented region. The PGMEA solution of the block copolymer described in Table 1 was applied to a guide substrate, and the coating film was baked at 90 °C for 60 seconds to form a layer containing the block copolymer having the film thickness t (nm) described in Table 1. Annealing was performed on the layer containing the block copolymer at 250 °C for 30 minutes to form a phase separation pattern.

[0082] <Evaluation of LER (Line Edge Roughness)> From the obtained phase separation structure, PMMA (or a copolymer block derived from methyl methacrylate) was selectively removed to form an LS pattern. Regarding the obtained LS pattern, an SEM image was acquired with a CD-SEM (CG6300 manufactured by Hitachi High-Tech Corporation), and the acquired SEM image was analyzed with MetroLER to obtain the LER. Specifically, the line edge width (the variation width from the reference straight line) was measured at 100 locations, and three times the standard deviation (σ) (unit: nm) obtained from the measurement results was calculated as the LER. The results are shown in Table 1.

[0083] <Evaluation of Alignment Mark Formation> An SEM image (10,000 times magnification) of the horizontal alignment region of the alignment mark was acquired and observed with a CD-SEM (CG6300 manufactured by Hitachi High-Tech Corporation), and evaluated according to the following criteria. The results are shown in Table 1. 〇: No extra irregularities such as a substantially circular shape were formed. ×: Extra irregularities such as a substantially circular shape were formed.

[0084]

Table 1

[0085] As shown in Table 1, it can be seen that by setting the film thickness t of the layer containing the block copolymer so that the relationship with the period L of the block copolymer satisfies a specific formula, the line roughness can be improved and the alignment mark can be formed well. 0

[0086] <Examples 2-1 to 2-10 and Comparative Examples 2-1 to 2-6>​ (Manufacture of a Structure Containing a Phase Separation Structure) A thermosetting neutralization film-forming resin composition, which is a PGMEA solution of a styrene / methyl methacrylate / hydroxyethyl methacrylate copolymer, was applied onto a 12-inch silicon wafer having a SOC (Spin on Carbon) film and a SOG (Spin on Glass) film as an antireflection film on the SOC film, using a spinner. A neutralization film was formed on the silicon wafer by baking the coated film at 240 °C for 60 seconds. An ArF photoresist for immersion lithography was applied onto the neutralization film to form a coated film. Then, the formed coated film was baked. Next, after exposing the baked coated film with an ArF immersion lithography machine, post-exposure baking was performed. After development, plasma etching, subsequent resist stripping, and post-baking were carried out to form a pattern of the neutralization film. Thereafter, a resin composition for forming a polystyrenized film, which is a propylene glycol monomethyl ether acetate (PGMEA) solution of a styrene / hydroxyethyl methacrylate copolymer, was applied onto the patterned neutralization film to form a coated film. The formed coated film was baked at 200 °C for 120 seconds, rinsed with OK73 thinner, and post-baked, whereby a circular polystyrenized film was arranged at positions corresponding to a hexagonal close-packed structure in plan view, and an evaluation guide substrate having a neutralization film formed therebetween was obtained. In the region where the alignment mark is formed, a polystyrenized film was formed in the horizontally oriented region, and a neutralization film was formed in the vertically oriented region. The PGMEA solution of the block copolymer described in Table 1 was applied onto the guide substrate, and the coated film was baked at 90 °C for 60 seconds to form a layer containing the block copolymer having the film thickness t (nm) described in Table 1. Annealing was performed on the layer containing the block copolymer at 250 °C for 30 minutes to form a phase separation pattern. In Comparative Examples 2-3, since pattern formation was not possible, misalignment evaluation was not performed.

[0087] (Misalignment Evaluation) From the obtained phase-separated structure, PMMA (or a copolymer block derived from methyl methacrylate) was selectively removed to form a CH pattern. Regarding the obtained CH pattern, an SEM image was acquired by CD-SEM (CG6300 manufactured by Hitachi High-Tech Corporation), and the acquired SEM image was analyzed with MetroLER to determine the misalignment. Specifically, the distance between the centers of gravity of the holes was measured at 5000 locations, and three times the standard deviation (σ) (unit: nm) obtained from the measurement results was calculated as the misalignment. The results are shown in Tables 2 and 3.

[0088] <Evaluation of Alignment Mark Formation> An SEM image of the horizontal alignment region of the alignment mark was acquired and observed by CD-SEM (CG6300 manufactured by Hitachi High-Tech Corporation), and evaluated according to the following criteria. The results are shown in Tables 2 and 3. 〇: No extra unevenness such as a substantially circular shape was formed. ×: Extra unevenness such as a substantially circular shape was formed.

[0089]

Table 2

[0090]

Table 3

[0091] As shown in Tables 2 and 3, by setting the film thickness t of the layer containing the block copolymer so that the relationship with the period L of the block copolymer satisfies a specific equation, it can be seen that the misalignment of the cylinder structure can be improved and an alignment mark can be formed well. 0 ​

Claims

1. (a1) forming a layer containing a block copolymer on a substrate using a resin composition containing the block copolymer and having a thickness of t (nm); and (a2) phase-separating the layer into a cylindrical structure, In step (a1), the thickness t is set to the period L of the block copolymer. ０ (nm) is set so as to satisfy the following formula (a): (2) ０ +(3 ０．５ / 2LL ０ ×n)×0.9≦t≦(2L ０ +(3 ０．５ / 2LL ０ ×n)×1.1 (a) (In formula (a), n is an integer of 0 to 3.)

2. The method according to claim 1 , wherein n is an integer of 1 to 3.

3. (a1) forming a layer containing a block copolymer on a substrate using a resin composition containing the block copolymer and having a thickness of t (nm); and (a2) phase-separating the layer into a cylindrical structure, In step (a1), the thickness t is set to the period L of the block copolymer. ０ The method for improving the positional deviation of a cylinder structure and the formation of an alignment mark, wherein the relationship between the thickness of the cylindrical structure and the alignment mark (nm) is set to satisfy the following formula (a): (2) ０ +(3 ０．５ / 2LL ０ ×n)×0.9≦t≦(2L ０ +(3 ０．５ / 2LL ０ ×n)×1.1 (a) (In formula (a), n is an integer of 0 to 3.)

4. (b1) forming a layer containing a block copolymer on a substrate using a resin composition containing the block copolymer and having a thickness of t (nm); and (b2) phase separating the layer into a lamellar structure, In step (b1), the thickness t is set to the period L of the block copolymer. ０ (nm) is set so as to satisfy the following formula (b): (1.5L ０ +0.5L ０ ×m)×0.95≦t≦(1.5L ０ +0.5L ０ ×m)×1.05 (b) (In formula (b), m is an integer of 0 to 5.)

5. The method according to claim 4 , wherein m is an integer of 1 or more and 5 or less.

6. (b1) forming a layer containing a block copolymer on a substrate using a resin composition containing the block copolymer and having a thickness of t (nm); and (b2) phase separating the layer into a lamellar structure, In step (b1), the thickness t is set to the period L of the block copolymer. ０ (nm) is set so as to satisfy the following formula (b): (1.5L ０ +0.5L ０ ×m)×0.95≦t≦(1.5L ０ +0.5L ０ ×m)×1.05 (b) (In formula (b), m is an integer of 0 to 5.)

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